I've been enjoying myself trying to capture some data. I turned to Eta Carina now that M42 is getting lower and the Canberra glow is to the West.
I don't have guiding so my 2 min exposures aren't great. The outer areas are made worse due to no flattener, but I cropped the worst of it.
Anyway: 3 x 2 min, no noise reduction, 500D, Equinox ED80.
These were manually stacked in GIMP since I just can't make my DSS output look any good. BTW, that's why I had no noise reduction, I took bundles of darks, but as I say, ...DSS!!! So much to learn.
Nice shot Bruce. You've got your polar alignment going nicely and the EQ6 is doing its job well if you can get pretty round stars with 2' subs and no guiding.
What issues are you having with DSS? There are some really knowledgable and helpful folk around here. I'm not one of them but I *think* I've just tamed DSS after a bit of a struggle.
Gavin, the skies are reasonably dark except, particularly to the East and South.
Jon, I stack all my Lights (RAW), Darks, Flats and Bias in DSS and while I know the initial output can look like nothing at all, in this case I'm seeing a pretty decent amount of data, but when I try and process it in GIMP, I just can't work the levels and curves to bring out anything like the colour I get by manual stacking a few JPGs (as per attachment). Don't get me wrong, I'm quite pleased with what I produced, but I just feel there's probably more potential with all the RAW stacked data out of DSS.
I might mention that I spent quite a while trying to retain a decent image at 200kb for posting. I usually resize to 800 x default and then Save to Web in IrfanView but this gives quite poor results. This time I used Save As in GIMP and set the output quality to 30%. This put it to ~ 700kb. I then cropped the worst of my outer stars and then (through trial and error) resized the image until < 200kb. In this case it ended up ~ 1700 x default.
Bruce, you mention colour as the issue with the stacked DSS images. I had a lot of issues with colour - either no colour at all, or a peculiar green or magenta hue to the whole thing. The setting "Use Auto White Balance" in the DSLR setting section of DSS does the trick.
Then you still need to boost the saturation a whole lot in Photoshop (or GIMP). You mention the levels and curves tools. It's actually the saturation tool you need. Stretching the levels a lot will actually sap the colour, so you have to keep boosting saturation as you go.
You are getting great detail so it's worth aiming for a few more subs, calibrating (with darks flats and bias) and stacking in DSS and then stretching and saturating. You'll find that the more calibrated subs you can stack, the more you can stretch to bring out detail.
Btw, I just upload jpgs to IIS that are around 500-100kb, and the server seems to automatically resize them to under 200kb. Save you some effort.
Jon, thanks for the DSS tips, I will give those things a look at very soon. I had 10 subs of 2 mins, but 7 of them had pretty long stars; only 3 seemed good enough. I will have to try and get some more soon.
